A railway vehicle vibration damping device for suppressing vibration of a vehicle body in the right and left direction with respect to the running direction of the railway vehicle comprises for example a variable damping force damper interposed between the vehicle body and a bogie. A damping force required for suppressing the vehicle body vibration is determined from an angular speed in the yaw direction of the vehicle body in vehicle body center and a speed in the sway direction of the vehicle body, and a damping force of the variable damping force damper is adjusted to exert the determined damping force.
More specifically, a damping force required for vibration suppression in the yaw direction is calculated by multiplying a yaw rate by a distance from the vehicle body center to a bogie center and a control gain. A damping force required for suppressing vibration in the sway direction is calculated by multiplying the speed in the sway direction by the control gain. The damping force to be generated by the variable damping force damper is calculated by adding the damping force for the vibration suppression in the yaw direction and the damping force for vibration suppression in the sway direction.
JP 2003-320931A published by the Japan Patent Office proposes that variable damping force dampers for suppressing vibration in the yaw direction and in the sway direction are respectively provided between a vehicle body of a railway vehicle and a front bogie for supporting a vehicle body front part and between the vehicle body and a rear bogie for supporting a vehicle body rear part.